1. Field of the Invention
The invention relates to an improved axle suspension system for vehicles, such as mobile homes, recreational vehicles, travel or utility trailers, or the like, and more particularly to such systems employing leaf springs resiliently supporting such vehicles.
2. Description of the Prior Art
Prior art vehicle suspension systems frequently include a pair of longitudinally-extending arcuate leaf springs secured to opposite ends of a laterally-extending axle. Typically, the vehicle's load is transferred to the ends of each leaf spring through a pair of longitudinally-spaced hangers fixed to the vehicle's frame.
Generally, one end of the leaf spring is restrained longitudinally and laterally by its hanger. Thus the longitudinal position at which the vehicle's load is transferred to the restrained end of the leaf spring is fixed to the vehicle frame. The opposite end of the leaf spring is also restrained laterally but is free to extend or retract longitudinally relative to a longitudinally fixed position at which the hanger engages the free end of the leaf spring. Thus in the prior art suspension systems, the longitudinal position at which the vehicle's load is transferred to the free end of leaf spring is longitudinally fixed relative to the leaf spring's restrained end.
When the leaf spring of such prior art suspension systems deflects, the axle moves closer to the load-transfer position at the free end of the leaf spring and farther from the load-transfer position at the restrained end of the leaf spring. As a result, the load distribution between the ends of the leaf spring varies as the leaf spring deflects.